Discriminating between first- and second-order cognition in first-episode paranoid schizophrenia*

Introduction: An impairment of visually perceiving backward masked stimuli is commonly observed in patients with schizophrenia, yet it is unclear whether this impairment is the result of a deficiency in first or higher order processing and for which subtypes of schizophrenia it is present.

Methods: Here, we compare identification (first order) and metacognitive (higher order) performance in a visual masking paradigm between a highly homogenous group of young first-episode patients diagnosed with paranoid schizophrenia (N?=?11) to that of carefully matched healthy controls (N?=?13).

Results: We find no difference across groups in first-order performance, but find a difference in metacognitive performance, particularly for stimuli with relatively high visibility.

Conclusions: These results indicate that the masking deficit is present in first-episode patients with paranoid schizophrenia, but that it is primarily an impairment of metacognition.     

Impaired facial and vocal emotion decoding in schizophrenia is underpinned by basic perceptivo-motor deficits*

Introduction: Emotional decoding impairments have been largely demonstrated in schizophrenia for facial and prosodic stimuli, when presented separately. Nevertheless, the exploration of crossmodal integration has been far less considered, despite its omnipresence in daily social interactions. Moreover, the role played by basic visuo-motor impairments in unimodal and crossmodal decoding remains unexplored.

Methods: Thirty-two patients were compared with 32 matched controls in an emotional decoding task including unimodal (visual and auditory) and crossmodal (congruent and incongruent) conditions. A control perceptive task was also conducted to take potential low-level perceptual deficits into account.

Results: Schizoprenic patients presented lower performance and higher reaction times for both unimodal tasks (visual and auditory) and crossmodal conditions. Moreover, reaction times for the visuo-perceptive task were also significantly longer for patients compared to controls.

Conclusions: The consistency of the results across unimodal and crossmodal tasks suggests a globalised emotional impairment in schizophrenia, independent of the sensorial modality and crossmodal nature of the stimuli. Centrally, given the results in the visuo-perceptive task, the impairments observed for emotional recognition appears at least partly explained by primary cognitive deficits, namely reduced processing speed.     

Enlarged temporal integration window in schizophrenia indicated by the double-flash illusion

Introduction: In the present study we were interested in the processing of audio-visual integration in schizophrenia compared to healthy controls. The amount of sound-induced double-flash illusions served as an indicator of audio-visual integration. We expected an altered integration as well as a different window of temporal integration for patients.

Methods: Fifteen schizophrenia patients and 15 healthy volunteers matched for age and gender were included in this study. We used stimuli with eight different temporal delays (stimulus onset asynchronys (SOAs) 25, 50, 75, 100, 125, 150, 200 and 300?ms) to induce a double-flash illusion. Group differences and the widths of temporal integration windows were calculated on percentages of reported double-flash illusions.

Results: Patients showed significantly more illusions (ca. 36–44% vs. 9–16% in control subjects) for SOAs 150–300. The temporal integration window for control participants went from SOAs 25 to 200 whereas for patients integration was found across all included temporal delays. We found no significant relationship between the amount of illusions and either illness severity, chlorpromazine equivalent doses or duration of illness in patients.

Conclusions: Our results are interpreted in favour of an enlarged temporal integration window for audio-visual stimuli in schizophrenia patients, which is consistent with previous research.     

Language abnormality in deaf people with schizophrenia: a problem with classifiers

Introduction: Although there is evidence for language abnormality in schizophrenia, few studies have examined sign language in deaf patients with the disorder. This is of potential interest because a hallmark of sign languages is their use of classifiers (semantic or entity classifiers), a reference-tracking device with few if any parallels in spoken languages. This study aimed to examine classifier production and comprehension in deaf signing adults with schizophrenia.

Method: Fourteen profoundly deaf signing adults with schizophrenia and 35 age- and IQ-matched deaf healthy controls completed a battery of tests assessing classifier and noun comprehension and production.

Results: The patients showed poorer performance than the healthy controls on comprehension and production of both nouns and entity classifiers, with the deficit being most marked in the production of classifiers. Classifier production errors affected handshape rather than other parameters such as movement and location.

Conclusions: The findings suggest that schizophrenia affects language production in deaf patients with schizophrenia in a unique way not seen in hearing patients.     

Systematic overview of neuroanatomical differences in ADHD: Definitive evidence

Objectives: This article seeks to identify neuroanatomical differences in ADHD through an overview of systematic reviews that report encephalic differences compared to a control group in volume, area, activation likelihood or chemical composition.

Methods: We conducted a systematic search using Cochrane guidelines and PRISMA criteria in PubMed, Scopus, Web of Science, Cochrane Database of Systematic Reviews and Database of Abstracts of Reviews of Effects.

Results: Results revealed broad encephalic involvement that includes a functional frontal and cingulate hypoactivation and structural differences in corpus callosum, cerebellum and basal nuclei.

Conclusions: ADHD symptoms might be due to a multi-network unbalanced functioning hypothesis.     

Evidence of absence: no relationship between behaviourally measured prediction error response and schizotypy

Introduction: The predictive processing framework has attracted much interest in the field of schizophrenia research in recent years, with an increasing number of studies also carried out in healthy individuals with nonclinical psychosis-like experiences. The current research adopted a continuum approach to psychosis and aimed to investigate different types of prediction error responses in relation to psychometrically defined schizotypy.

Methods: One hundred and two healthy volunteers underwent a battery of behavioural tasks including (a) a force-matching task, (b) a Kamin blocking task, and (c) a reversal learning task together with three questionnaires measuring domains of schizotypy from different approaches.

Results: Neither frequentist nor Bayesian statistical methods supported the notion that alterations in prediction error responses were related to schizotypal traits in any of the three tasks.

Conclusions: These null results suggest that deficits in predictive processing associated with clinical states of psychosis are not always present in healthy individuals with schizotypal traits.     

Do patients with different psychiatric disorders show altered social decision-making? A systematic review of ultimatum game experiments in clinical populations

Background: Impairments in social functioning are a common feature of psychiatric disorders. Game paradigms pose a unique way for studying how people make decisions in interpersonal contexts. In the last decade, researchers have started to use these paradigms to study social decision-making in patients with psychiatric disorders.

Purpose: The aim of this systematic literature review is to summarise the currently available evidence on the behaviour of patients with psychiatric disorders in the commonly used Ultimatum Game (UG).

Method: A systematic literature search including MEDLINE, PsycINFO, PSYNDEXplus Tests, PSYNDEXPLUS Literature, EBM Reviews—Cochrane Central Register of Controlled Trials, Embase and PASCAL was performed via the Ovid interface.

Results: We found evidence for alterations in UG behaviour for patients with frontotemporal dementia, schizophrenia, affective disorders, alcohol, cocaine, heroin and 3,4-methylenedioxymethamphetamine consumption, alcohol dependence, anxiety disorders, borderline personality disorder, autism, Tourette syndrome and oppositional defiant disorder.

Conclusion: There is some evidence that different psychiatric disorders might go along with alterations in social decision-making. However, in general, data are currently limited and studies are hard to compare due to differences in methodologies.     

Effects of cognitive remediation therapy on neurocognition and negative symptoms in schizophrenia: an Italian naturalistic study

Introduction: Cognitive remediation therapy (CRT) has been reported to positively affect neurocognitive processes among patients with schizophrenia; however, the degree to which changes in cognition is linked to improved clinical symptoms, remains poorly understood. The current study aimed to investigate whether cognitive gains were associated to improvements in negative symptoms’ severity in patients with schizophrenia living in two Italian psychiatric facilities.

Methods: Patients with a diagnosis of schizophrenia were consecutively assigned to CRT (n?=?33) and compared with an historical control group (n?=?28). Assessments were performed at baseline and post-treatment using a neuropsychological battery (Trail Making Test A and B, Self-Ordered Pointing Task, California Verbal Learning Test), along with clinical and functioning measures.

Results: Visual attention (TMT-A score change) was found as the only significant predictor of improvement in negative symptoms subscale of the Positive and Negative Syndrome Scale. Furthermore, a mediation path analysis confirmed that better performance in visual attention acts as mediator of the positive association between CRT intervention and lower post-treatment negative symptoms score.

Conclusions: CRT can have a positive impact on a measure of visual attention in patients with schizophrenia and on negative symptoms reduction that is mediated by this significant intervention effect.     

Emotion recognition and social skills in child and adolescent offspring of parents with schizophrenia

Introduction: Emotion recognition, a social cognition domain, is impaired in people with schizophrenia and contributes to social dysfunction. Whether impaired emotion recognition emerges as a manifestation of illness or predates symptoms is unclear. Findings from studies of emotion recognition impairments in first-degree relatives of people with schizophrenia are mixed and, to our knowledge, no studies have investigated the link between emotion recognition and social functioning in that population.

Methods: This study examined facial affect recognition and social skills in 16 offspring of parents with schizophrenia (familial high-risk/FHR) compared to 34 age- and sex-matched healthy controls (HC), ages 7–19.

Results: As hypothesised, FHR children exhibited impaired overall accuracy, accuracy in identifying fearful faces, and overall recognition speed relative to controls. Age-adjusted facial affect recognition accuracy scores predicted parent’s overall rating of their child’s social skills for both groups.

Conclusions: This study supports the presence of facial affect recognition deficits in FHR children. Importantly, as the first known study to suggest the presence of these deficits in young, asymptomatic FHR children, it extends findings to a developmental stage predating symptoms. Further, findings point to a relationship between early emotion recognition and social skills. Improved characterisation of deficits in FHR children could inform early intervention.     

Down the rabbit hole: assessing the influence of schizotypy on the experience of the Barbie Doll Illusion

Introduction: “Body swapping” illusions have been used to explore factors contributing to the experience of “owning” an artificial body. Preliminary research indicated that those people diagnosed with schizophrenia experience more vivid illusions of this kind than do “normal” individuals.

Objectives: Here, we explored whether participants who rated themselves “high” on the cognitive-perceptual factor of the Schizotypal Personality Questionnaire (SPQ) experienced a more compelling sense of immersion in a variation of the body swapping illusion: The Barbie Doll Illusion. We also hypothesised that these individuals would experience a change in size perception when immersed in the illusion.

Method: Forty-four participants wore a pair of Head-Mounted Display goggles connected to a video-camera, and thus a doll’s body replaced their own body in their visual field. In two conditions, touch was either applied synchronously or asynchronously to the doll’s and each participant’s leg. After each condition, participants filled out a questionnaire relating to their experience in the illusion. When both conditions were completed, they filled out the SPQ.

Results: Our first hypothesis was confirmed, which suggested that people with higher cognitive-perceptual SPQ scores do indeed experience a more compelling Barbie Doll Illusion; however, our second hypothesis was not supported.

Conclusion: Our study demonstrated, for the first time, that proneness to the positive and interpersonal factors of schizotypy in a normal population is sufficient to produce a compelling sense of swapping bodies.     

ALK protein expression in pulmonary adenocarcinoma of Tunisian patients

Background. It is now necessary to determine ALK status in order to use targeted therapy. Aim: herein, we assess immunohistochemical profile of ALK protein in a series of Tunisian patients with pulmonary adenocarcinoma.

Materials and Methods. ALK protein expression was studied applying the D5F3 antibody with a fully automated Ventana CDx technique on a series of 19 patients.

Results. Positive ALK expression was found in one case (5.2%) corresponding to a papillary adenocarcinoma which showed a strong granular and homogenous cytoplasmic staining. The patient was a 30-years-old woman.

Conclusion. The frequency of positive ALK expression based on immunohistochemistry in our series was similar to that reported in the world literature.     

Neurocognitive insight and executive functioning in schizophrenia

Introduction. This study explored whether integrity of executive functioning is required for good neurocognitive insight (NI) in subjects with schizophrenia.

Methods. NI was measured by subtracting executive difficulties (errors in the Modified Card Sorting Task) from executive cognitive complaints (Subjective Scale to Investigate Cognition in Schizophrenia) in 40 outpatients with schizophrenia and 42 normal controls. The schizophrenia sample was a priori divided into two subgroups on the basis of executive level. Multivariate analyses were conducted to compare groups and to control for potential confounding factors.

Results. Only the schizophrenia dysexecutive subgroup had a poorer NI compared to normal controls. Group differences remained significant after adjustment for potential confounding factors (education, depression, anxiety and self-esteem).

Conclusion. These results provide support for the hypothesis that executive dysfunctioning is a limiting factor for NI, independently from depressive and anxiety symptoms.     

The Orientalisation of North Africa: New hints from the study of autosomal STRs in an Arab population

Background: Recent genomic analyses suggest that the current North African gene pool was mainly influenced by population flow coming from the East that altered the genetic structure of autochthonous Berber populations. Such genetic flow has not been extensively addressed yet using North African populations of Middle-eastern origin as reference.

Aim: To discern the Middle-eastern component in the genetic background of Tunisian Arabs and evaluate the extent of gene flow from the Middle East into North African autochthonous Berber populations.

Subjects and methods: This study has examined 113 Tunisians of well-known Arabian origin from Kairouan region, using 15 autosomal Short Tandem Repeats (STRs) loci.

Results: No deviations from Hardy-Weinberg equilibrium were observed and all loci presented high levels of heterozygosity. Principal coordinate and STRUCTURE analyses were consistent in clustering together North African and Middle Eastern populations, likely reflecting the recent gene flow from the East dating back to the Arab conquest period. This demographic migration and the Arabisation process that submerged the original Berber language and customs seems to have be accompanied by substantial gene flow and genetic admixture.

Conclusion: This study represents an additional step to obtain a comprehensive understanding of the complex demographic history of North African populations.     

Testing times: identifying puberty in an identified skeletal sample

Background: Identifying the onset of puberty in skeletal remains can provide evidence of social changes associated with the onset of adulthood.

Aim: This paper presents the first test of a skeletal method for identifying stages of development associated with the onset of puberty in a skeletal sample of known age and cause of death.

Materials and methods: Skeletal methods for assessing skeletal development associated with changes associated with puberty were recorded in the identified skeletal collection in Coimbra, Portugal. Historical data on the onset of menarche in this country are used to test the method.

Results: As expected, females mature faster than their male counterparts. There is some side asymmetry in development. Menarche was found to have been achieved by an average age of 15.

Conclusions: Asymmetry must be taken into account when dealing with partially preserved skeletons. Age of menarche is consistent, although marginally higher, than the age expected based on historical data for this time and location. Skeletal development in males could not be tested against historical data, due to the lack of counterpart historical data. The ill health known to be present in this prematurely deceased population may have delayed skeletal development and the onset of puberty.     

Allergen immunotherapy in allergic rhinitis: current use and future trends

Introduction: Type-1 allergies are among the most chronic common diseases of humans. Allergen immunotherapy (AIT) is the only causative and disease-modifying treatment option besides allergen avoidance. Severe systemic adverse allergic reactions may be induced by every AIT treatment. Different approaches have been used to provide safer AIT preparations to lower or even totally overcome this risk.

Areas covered: A structured literature recherche in Medline and Pubmed under inclusion of national and international guidelines and Cochrane meta-analyses has been performed aiming at reviewing clinical use of such approaches in AIT.

New allergen preparations may include allergoids, recombinant allergens (recA) and modified recombinant allergens (recA) in subcutaneous as well as in mucosal immunotherapies (application e.g. using bronchial, nasal, oral and sublingual application) with sublingual being the established mucosal application route and new ways of application like intralymphatic and epicutaneous immunotherapy.

Expert commentary: Immune-modifying agents like Virus-like particles and CpG-motifs, adjuvants like MPL and aluminum hydroxide are evaluated and found to increase and direct the immunological response toward immunological tolerance.

New forms of allergen extracts can improve safety and efficacy of AIT and may change our way of performing allergen immunotherapy in the future.     

Y-Chromosome haplotypes reveal relationships between populations of the Arabian Peninsula,North Africa and South Asia

Background: The United Arab Emirates (UAE) is positioned at the crossroads of human migration out of Africa and through to Asia and Europe.

Aim: To compare the degree of genetic diversity of the Arabian UAE population with populations in other countries from the Middle East, South Asia and North Africa.

Subjects and methods: Twenty-seven Y-STR were analysed in 217 individuals. Y-STR haplotypes from this study were compared to population data stored in YHRD, using MDS and AMOVA.

Results: Two hundred and twelve haplotypes were observed in the 217 individuals studied. Although the reduction in Y-STR loci from 27 to 17 resulted in a decrease in discriminatory power, comparisons of populations were possible. The UAE population clustered closer with other populations of the Middle East. The South Asian and North African populations were separated by Middle Eastern populations in between both clusters.

Conclusion: This is the first study to report the diversity of a population of the Arabian Peninsula using 27 Y-STR. MDS plots show that Middle Eastern populations are positioned in the centre, with African, Asian and European populations around the Arab population cluster. The findings of this study are consistent with this region being at the epicentre of human migration between continents.     

Evaluating mtDNA patterns of genetic isolation using a re-sampling procedure: A case study on Italian populations

Background: A number of studies which have investigated isolation patterns in human populations rely on the analysis of intra- and inter-population genetic statistics of mtDNA polymorphisms. However, this approach makes it difficult to differentiate between the effects of long-term genetic isolation and the random fluctuations of statistics due to reduced sample size.

Aim: To overcome the confounding effect of sample size when detecting signatures of genetic isolation.

Subjects and methods: A re-sampling based procedure was employed to evaluate reduction in intra-population diversity, departure from surrounding genetic background and demographic stationarity in 34 Italian populations subject to isolation factors.

Results: Signatures of genetic isolation were detected for all three statistics in seven populations: Pusteria valley, Sappada, Sauris, Timau settled in the eastern Italian Alps and Cappadocia, Filettino and Vallepietra settled in the Appenines. However, this study was unable to find signals for any of the statistics analysed in 19 populations. Finally, eight populations showing signals of isolation were found for one or two statistics.

Conclusion: The analysis revealed that the use of population genetic statistics combined with re-sampling procedure can help detect signatures of genetic isolation in human populations, even using a single, although highly informative, locus like mtDNA.